A recent evolution in neurosurgical technologies has led to a way to treat the most serious kinds of brain tumors while preserving brain function. Latest technology uses a large bore access tube, advanced imaging of tracts in the brain and a computerized brain navigation system, which allows physicians to navigate the brain with unprecedented clarity to target and remove deep-seated brain tumors, abscesses and hemorrhages with much less disruption of tissue than with microscopic surgical techniques. While individual technologies have been available for more than a decade, they have primarily been used independent of one another. Neurosurgery has now evolved by using a “6 Pillar Approach”. The Pillars of the approach include: brain imaging, neuro-navigation, access, high-definition optics, resection (removal) of the abnormality, and tissue collection for regenerative medicine options.
This procedure is an improvement to traditional open surgery because a small opening is created to access deep in the brain, so less of the brain is exposed, and there is less disruption to the brain tissue.
The currently used rigid large access tube devices provide access and visualization of lesions in the subcortical space of the brain, and decrease trauma to the brain tissue. These devices typically have an obturator uniquely designed with a sharp tip that is intended to displace tissue of the brain during advancement to the targeted abnormality. A rigid sheath remains in the brain after the obturator is removed to serve as a protective portal for surgeons to easily maintain access to the surgical site. Rigid access tube devices do not vary by abnormality type, but rather they are adapted to where the abnormality is located, and they provide a pathway to deep locations within the brain.
The difference from a surgical standpoint is that surgeons using the rigid access devices enter the brain through the sulci, the natural folds of the brain, to displace the critical structures in the white matter to reach the abnormality, thereby potentially reducing tissue damage. While existing minimally invasive approaches use small openings, surgeons using the rigid access devices still cut through the brain's white matter—tissue responsible for any number of cognitive and functional responses—to reach the target abnormality. The rigid access devices attempt to displace white matter but are quite large in diameter.
These rigid access devices attempt to provide atraumatic access to the brain abnormality by navigating through the delicate folds and fibers of the brain. The two-piece system has a clear plastic sheath around a smooth, cylindrical tool with a specially designed tip. The rigid access device enters the brain through an 18 mm diameter opening. Once at the location of the abnormality, the surgeon removes the obturator from the tube, leaving the tube in place to create a portal or narrow corridor through which the surgeon operates.
It would be useful to provide an improvement to neurosurgical access that leverages some of the fundamentals described above but with an even more minimally invasive approach that provides less injury and trauma to the brain's white matter.
It is preferred to navigate through the natural folds of the brain's white matter as opposed to cutting, tearing, or other tissue disruption. This would minimize stress forces and pressure that are harmful to brain tissue.
It would be useful to provide an access sheath for protection of brain matter for neurosurgery. It would provide one or more of the following benefits:                Protecting white matter of the brain from the placement and manipulation of surgical instruments both during the initial placement and during manipulation and exchange        Reducing sheer forces and traumatic injury to the brain tissue to protect white matter        Providing a guide port to help direct instruments into position        Splint and protect white matter to help open and provide access        Protect instruments and especially endoscope's image clarity        